I found this pretty cool app for the iphone and ipad which is now also available for android too.
Its a piano chord finder so you can take any melody and find the chords to it in a flash.
The idea is that you type in to the app the notes of the melody or the notes that you would like to harmonise and the app will tell you which are the chords that will go with that particular note. You choose the chords and build them up allowing the app to play the chords as you touch them.
As well as hearing the audio, which can be piano or organ sounds, you also get to see the chord as it should be played on the piano keyboards.
To find the app, you have to search the app store for 'Piano Harmony MIDI Studio Pro'.
The way the app functions is quite basic as you don’t always necessarily harmonise each note of a melody. The chords at first glimpse are simple major chords but there is an option to change the chord database so that it will give you Jazz chords or Gospel chords as well.
All in all the app is a little clumsy to use but for those who don’t really know anything about harmony then it can be of great use… for those who do understand about music theory and chords then it can be entertaining for a while and as the app is free there is nothing to loose.